April 2

Plan:

• Questions
• The story of the cubic

Discussion:
The discussion page can be found here, for observations and remarks.

Here's a link to Barry Mazur's Imagining Numbers (particularly the square root of minus fifteen): http://www.amazon.com/Imagining-Numbers-particularly-square-fifteen/dp/0312421877/ref=sr_1_1?s=books&ie=UTF8&qid=1364930001&sr=1-1&keywords=barry+mazur

It's only $12. Read the reviews and decide if it's for you. Typical cubic equation:$ax^3 +bx^2 + cx +d$Cardono's solution to:$x^3 = cx+d$(The rule and examples are found on pg 230 of the text) if:${( \frac{c}{3})}^3 \leq {( \frac{d}{2})}^2$do the following steps:$\\ 1. {( \frac{d}{2})}^2 - {( \frac{c}{3})}^3 \\ 2. \sqrt{{( \frac{d}{2})}^2 - {( \frac{c}{3})}^3} \\ 3. \sqrt {d/2 - \sqrt{ {( \frac{d}{2})}^2 - {( \frac{c}{3})}^3}}=u \\ 4. \sqrt {d/2 + \sqrt{ {( \frac{d}{2})}^2 - { ( \frac{c}{3})}^3}}=v \\ 5. x= u+v\$

Note that this is only one solution to the equation and it is possible that there are others

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License